Creating an events and membership site- advise sought

Got a new project and thought I would ask if someone could help / advise. Need to create a website for a company that does 5 events a month. So the idea is to create something like a membership site and use an Eventbrite plugin to post the actual events.

Similar to this site: https://www.4networking.biz/

And was thinking of this theme to start with and then customise to our need.

http://themeforest.net/item/socialize-multipurpose-buddypress-theme/full_screen_preview/12897637

So seeking advice on the following.

1.

I want to integrate Eventbrite on this.. so – is there a plugin that can do it easily?

Or do you suggest setting up a multisite and then using a spate WP installation for the events side of things. For example this theme: http://www.showthemes.com/emt-demo/registration/

Thoughts on the above is most appreciated.

2.

What would be the easiest way to monetise this ? i.e we want to do it for free initially and then perhaps charge users to be a member from there on?

Not quite sure if the theme in question can handle this – so is there any other way . any other plugin I can use? Mind you events will always be for free, just may want to charge the members a monthly/yearly fee going forward.

Many thanks in advance and wishing you all there a very happy new year!!!